Leonardo da Vinci designed an odometer to measure distance by counting wheel rotations.
His cart-like device used a wheel that turned as the cart moved. A geared mechanism transferred the wheel’s movement to a container or display that recorded increments of travel, allowing the operator to estimate distance. Leonardo’s version was intended for surveying and engineering work rather than for measuring the speed of a vehicle.
An odometer and a pedometer both count movement, but an odometer is associated with distance traveled by a vehicle or wheel, while a pedometer counts a person’s steps. Leonardo’s device also differed from a compass, which establishes direction. The design reflects his practical interest in mapping, military planning, and construction. Although ancient engineers had used related wheel-based measuring devices, Leonardo’s notebook drawing is a well-known Renaissance example of an odometer concept using gears to convert rotation into a distance record.